holographic data storage breaks the surface barrier

We are reaching the tangible limits of storage capacity of data as individual bits on media surfaces. In the case of holographic storage, information is encoded in photosensitive material as three- dimensional laser interference patterns. The capacity to store information within the thickness of information recordable media, not just on its surface, offers the possibility of orders-of-magnitude more storage capacity than traditional information media. Holographic data storage may provide more quick access quicknesss and also high storage compression. Laser beams do not have inertia like the mechanical reading and writing elements of traditional, rotating media -- so the rays can be moved quickly to illuminate sequential pages of data. However, there are hurdles to be overcome. One hurdle for holotechnology data storage is that the clarity of each page of information stored volumetrically throughout the detail of photosensitive media decreases when there are too many pages saved in the media. Also, Edmund Scientific Co. includes coverage of holotech related technologies.

In order to store an orderly holographic picture, the light waves used have to move in a wave-synchronous (ordered and synchronized) manner. Lasers are used caused by their wave-synchronous light waves. Generally a single laser ray is divided with a partially-reflective reflective panel into the signal ray and reference beams. For recording a holographic image of an object, the signal beam goes through an expander lens, shines on the object, and then bounces off the object onto three- dimensional, optically sensitive optical media like a crystal or polymer. For holographic recording of data, a Spatial Light Modulator encodes a slice of information into the signal ray that shines onto the holotechnology media. The reference and signal beams of light overlap in the storage material. The resulting configuration of overlapping peaks and troughs makes molecular reactions that encode the holographic picture in the optical media for later retrieval. Also, Interactive Reality Virtual Networks provides information on this topic.

Holographic Data Storage covers related topics in detail.